CVE-2018-12387

A vulnerability where the JavaScript JIT compiler inlines Array.prototype.push with multiple arguments that results in the stack pointer being off by 8 bytes after a bailout. This leaks a memory address to the calling function which can be used as part of an exploit inside the sandboxed content process. This vulnerability affects Firefox ESR < 60.2.2 and Firefox < 62.0.3.

Weakness

The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.

Affected Software

Name	Vendor	Start Version	End Version
Enterprise_linux_desktop	Redhat	6.0 (including)	6.0 (including)
Enterprise_linux_desktop	Redhat	7.0 (including)	7.0 (including)
Enterprise_linux_server	Redhat	6.0 (including)	6.0 (including)
Enterprise_linux_server	Redhat	7.0 (including)	7.0 (including)
Enterprise_linux_server_aus	Redhat	7.6 (including)	7.6 (including)
Enterprise_linux_server_eus	Redhat	7.5 (including)	7.5 (including)
Enterprise_linux_server_eus	Redhat	7.6 (including)	7.6 (including)
Enterprise_linux_server_tus	Redhat	7.6 (including)	7.6 (including)
Enterprise_linux_workstation	Redhat	6.0 (including)	6.0 (including)
Enterprise_linux_workstation	Redhat	7.0 (including)	7.0 (including)
Red Hat Enterprise Linux 6	RedHat	firefox-0:60.2.2-1.el6	*
Red Hat Enterprise Linux 7	RedHat	firefox-0:60.2.2-1.el7_5	*
Firefox	Ubuntu	bionic	*
Firefox	Ubuntu	cosmic	*
Firefox	Ubuntu	devel	*
Firefox	Ubuntu	disco	*
Firefox	Ubuntu	eoan	*
Firefox	Ubuntu	focal	*
Firefox	Ubuntu	groovy	*
Firefox	Ubuntu	hirsute	*
Firefox	Ubuntu	impish	*
Firefox	Ubuntu	jammy	*
Firefox	Ubuntu	kinetic	*
Firefox	Ubuntu	lunar	*
Firefox	Ubuntu	mantic	*
Firefox	Ubuntu	noble	*
Firefox	Ubuntu	trusty	*
Firefox	Ubuntu	upstream	*
Firefox	Ubuntu	xenial	*
Mozjs38	Ubuntu	bionic	*
Mozjs38	Ubuntu	esm-apps/bionic	*
Mozjs38	Ubuntu	upstream	*
Mozjs52	Ubuntu	bionic	*
Mozjs52	Ubuntu	cosmic	*
Mozjs52	Ubuntu	disco	*
Mozjs52	Ubuntu	eoan	*
Mozjs52	Ubuntu	esm-apps/focal	*
Mozjs52	Ubuntu	esm-infra/bionic	*
Mozjs52	Ubuntu	focal	*
Mozjs52	Ubuntu	groovy	*
Mozjs52	Ubuntu	upstream	*
Thunderbird	Ubuntu	bionic	*
Thunderbird	Ubuntu	cosmic	*
Thunderbird	Ubuntu	devel	*
Thunderbird	Ubuntu	disco	*
Thunderbird	Ubuntu	eoan	*
Thunderbird	Ubuntu	focal	*
Thunderbird	Ubuntu	groovy	*
Thunderbird	Ubuntu	hirsute	*
Thunderbird	Ubuntu	impish	*
Thunderbird	Ubuntu	jammy	*
Thunderbird	Ubuntu	kinetic	*
Thunderbird	Ubuntu	lunar	*
Thunderbird	Ubuntu	mantic	*
Thunderbird	Ubuntu	noble	*
Thunderbird	Ubuntu	trusty	*
Thunderbird	Ubuntu	upstream	*
Thunderbird	Ubuntu	xenial	*

Extended Description

Input validation is a frequently-used technique for checking potentially dangerous inputs in order to ensure that the inputs are safe for processing within the code, or when communicating with other components. Input can consist of:

Data can be simple or structured. Structured data can be composed of many nested layers, composed of combinations of metadata and raw data, with other simple or structured data. Many properties of raw data or metadata may need to be validated upon entry into the code, such as:

Implied or derived properties of data must often be calculated or inferred by the code itself. Errors in deriving properties may be considered a contributing factor to improper input validation.

Potential Mitigations

Assume all input is malicious. Use an “accept known good” input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, “boat” may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as “red” or “blue.”
Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code’s environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.
For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
Even though client-side checks provide minimal benefits with respect to server-side security, they are still useful. First, they can support intrusion detection. If the server receives input that should have been rejected by the client, then it may be an indication of an attack. Second, client-side error-checking can provide helpful feedback to the user about the expectations for valid input. Third, there may be a reduction in server-side processing time for accidental input errors, although this is typically a small savings.
Inputs should be decoded and canonicalized to the application’s current internal representation before being validated (CWE-180, CWE-181). Make sure that your application does not inadvertently decode the same input twice (CWE-174). Such errors could be used to bypass allowlist schemes by introducing dangerous inputs after they have been checked. Use libraries such as the OWASP ESAPI Canonicalization control.
Consider performing repeated canonicalization until your input does not change any more. This will avoid double-decoding and similar scenarios, but it might inadvertently modify inputs that are allowed to contain properly-encoded dangerous content.

NVD	https://nvd.nist.gov/vuln/detail/CVE-2018-12387
CWE	https://cwe.mitre.org/data/definitions/20.html

Improper Input Validation

Weakness

Affected Software

Extended Description

Potential Mitigations

References

CVE-2018-12387

Improper Input Validation

Weakness

Affected Software

Extended Description

Potential Mitigations

Related Attack Patterns

References